(Reuters) - Roger Federer celebrated his return to the top of the world rankings with his second title of the season, swatting aside Grigor Dimitrov 6-2 6-2 in the final of the ABN AMRO World Tournament in Rotterdam on Sunday.

Federer, 36, who guaranteed becoming the oldest ever ATP world number one by reaching the semi-final, had won all six of his previous meetings with Dimitrov and was in command throughout Sunday’s 55-minute final.

He broke the Bulgarian opponent early in the contest and cruised to a one-set lead at the Ahoy Rotterdam.

Playing flawless tennis, the 20-times major winner carried the momentum forward in the second set to seal a 97th career title and third in Rotterdam having won in 2005 and 2012.

The Swiss, who won the Australian Open last month for the second year in succession, also improved his head-to-head record against world number five Dimitrov to 7-0.

“It’s definitely one of those weeks I will never forget in my life,” Federer, who last topped the standings in 2012, said.

“It’s unbelievable to get my 97th title and get back to world number one. It’s very special.”

Federer said he had expected a tougher afternoon against Dimitrov who will rise from five to four in the rankings.

“Grigor is a great player and a great athlete and he’s been playing super well in recent months,” he said.

“I thought that this wasn’t going to be the result, but he looked to be struggling a bit and I never looked back. I was able to execute my tennis the way I wanted to. I’m very happy.”